Why is my lavender turning brown?

QUESTION: Why is my lavender turning brown? I planted some and was hoping it would be a big part of my garden, and now it’s all dying and I’m distraught. – Tina O

JENNIFER POINDEXTER AT GARDENING CHANNEL REPLIES: There are a variety of reasons as to why your lavender is browning. Let’s discuss each possible cause and how you can (possibly) correct the issue:

1. Your Lavender Has a Fungal Disease

If you don’t grow lavender in ideal growing conditions, it runs the risk of becoming water-logged. When this occurs, the plant may develop root rot.

This disease causes the plant to brown. Once root rot sets in, it’s difficult to cure. Therefore, avoiding it is your best method. Ensure to plant lavender in an area with well-draining soil to avoid this problem.

2. Your Lavender Has Too Much (or Too Little) Moisture

If your plant receives too much water (or not enough) it can lead to the plant turning brown. Again, well-draining soil can assist if the plant becomes oversaturated.

During periods of heavy rain, ensuring the soil is loamy, may help the plant rebound from receiving too much water. If the plant is under watered, it’s best to practice the deep watering method.

This allows you to apply more water at a single time which should encourage a deeper root system and the plant should draw moisture from the ground between waterings.

It’s vital to test the soil regularly to know when the plant needs more water. When the soil is dry to your first knuckle, water the plant deeply again. This should help you avoid over or underwatering your lavender plant.

3. Your Lavender Has Too Much (or Too Little) Humidity

If your plant receives too much (or too little) humidity, this can cause the plant to brown. Too much humidity can be avoided by ensuring there’s at least one foot of space between each lavender plant.

This assists with providing adequate airflow. You may also prune to provide better airflow. If your lavender is browning due to too much humidity, it’s also wise to provide afternoon shade. 

Should your plant get brown and crunchy, this could mean it doesn’t have enough humidity. Avoid this by misting the plant with water. Finding the right balance in humidity, should help your plant maintain its beautiful color.

4. Your Lavender Is Invaded by Pests

Lavender does have common pests which impact it in its growing spaces. One of the most common issues is the aphid.

If you spot pests on your plants, be sure to treat the situation quickly with an insecticide. You may also try to handpick the pests or spray the plant with soapy water. This should help dislodge them.

Pests will suck the coloring out of your plant due to their feeding habits. Treating pest infestations promptly should help your plant rebound.

5. Your Lavender Needs Nutrients

When plants produce blooms during the growing season, it takes nutrients. Lavender may brown when it’s trying to produce but doesn’t have what it needs.

To avoid this issue, be sure to supply lavender with fertilizer twice each year. Apply a balanced fertilizer as the plant begins to produce.

Then apply a second dose after the first set of flowers fade. This can ensure your plant isn’t running on empty during the growing season.

6. Your Lavender Needs Pruning

Sometimes lavender plants turn brown due to their age. Plants may feel younger by pruning them.

If you see brown patches appearing in your plant, ensure none of the other issues mentioned here are occurring.

If they aren’t, then give your lavender plant a trim. Be careful not to remove more than 30% of the plant at a time. However, by cutting the plant back, it should turn back the clock. This should make for a younger, more productive plant.

7. Your Lavender Needs Adequate Growing Conditions

As mentioned earlier, if you don’t provide adequate growing conditions, your lavender plant could fall prey to disease.

Avoid these issues by ensuring you grow lavender in an area with full sunlight and well-draining soil. Most fungal issues thrive in areas that are cold and wet.

By planting in a space that drains excess water away quickly and also contains full sunlight, this should help deter diseases from forming. 

8. Your Lavender’s Growing Season Is Coming to an End

The last reason why your lavender plant may be turning brown is frost has occurred. Lavender should remain winter hardy in planting zones five through nine.

If frost has occurred, and you live in a hardiness zone, cut lavender back to soil level. Then apply a light layer of mulch or straw to insulate the roots over winter.

If you live in an area that gets snow regularly, this may insulate the plant without needing anything extra. Take these tips into consideration when overwintering your lavender plant.

You now have eight reasons why your lavender plant could be turning brown. Assess the situation and determine which of these things is behind the color change in your plant.

Then utilize the tips provided to rectify the situation. Hopefully, this will get your plant moving in a healthier direction, so you may enjoy your lavender in future years.

Learn More about Lavender

https://ucanr.edu/sites/EDC_Master_Gardeners/files/168086.pdf

https://extension.usu.edu/yardandgarden/research/english-lavender-in-the-garden

https://utgardens.tennessee.edu/lavender-the-useful-plant/